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Answer: D) 30</h3>
Angle of incidence always equals angle of reflection. Think of a tennis ball being hit into a wall. The ball will bounce off at the same angle that it approached with. The angles mentioned are formed through the line called the "normal", which is the line perpendicular to the surface.
Answer:
Solid materials that do not possess an orderly arrangement of atoms are called glasses (mineraloids).
Explanation:
A Mineraloid is a natural, inorganic, amorphous (lacking "defined chemical composition") solid body that does not exhibit crystallinity. It exhibits characteristics similar to those of minerals, but does not have the "ordered atomic structure" necessary to meet the definition of a mineral.
Glasses or colloids have a totally random structure on an atomic scale. They are amorphous and get the honorary name of mineraloid.
<u><em>Solid materials that do not possess an orderly arrangement of atoms are called glasses (mineraloids).</em></u>
